Wire joints are often used to connect multiple copper conductors using a tubular connector. The wires are placed in the tubular connector and crimped together. However, due to increases in the cost of copper, the use of aluminum cable has increased. Joining copper and aluminum requires a special connector compatible with aluminum because aluminum wiring has a thermal expansion rate that is different from that of copper. Without a connector designed for joining aluminum and copper, the connection may loosen over time and result in overheating.
The typical connector used to join conductors of copper and aluminum must be sized specifically for the application, and each wire size combination requires a compression wire joint that is specific to the application. As a result, an installer must carry a large supply of the various sizes of crimping dies that are specific to each application, and there exists a large potential for installation errors if the incorrect wire, connector, or die is used. With high voltage applications, errors by installers and loose connections can lead to failure of the connection, resulting in overheating or even fires.